What's the physical difference between ported manifolds and headers? How do they increase performance?

What are the pros/cons of each?

Ported manifolds are exhaust manifolds where the inner diameter has increased.
Pros: Long lasting. Exhaust Manifolds don't really go bad. Strong seal. No leaks. Cheap ($300.00)
Cons: Doesn't provide as much exhaust flow as headers.

For headers, each exhaust opening has its own separate long tube. This causes more exhaust flow.
Pros: More power, looks nice. Best bang-for-the-buck mod on a car.
Cons: Doesn't last as long as headers (100k). Could leak. Hard to install and use up more space. More expensive.

You can do a google search and see pictures and info of headers and manifolds.

Thanks.

So if I dropped $900 on the premium headers on pfyc, they would actually wear out around 100k? I had no idea...

I don't know what the life span of the TOGs are.

Stainless headers with a 3/8th flange will last along time. Jethot coated headers with a 3/8 flange will last a long time. Steel headers will corrode out in a couple of years.

100k was average for headers.

TOG headers look EXTREMELY strong. The only fear I have with them is leaks after 100k. Those particular headers look like they will last longer than 100k.

Also note if you want a turbo, it won’t fit with the headers.

I think the turbo kit comes with it's own headers.

Also, for the GT owners, like me, it's not worth putting on headers because of loss of low end torque. Ported exhaust manifolds would be better for GTs.

porting also reduces restriction by matching the diameter of the cylinder head runner to the manifold (intake and exhaust) so the air flows seamlessly

headers also transmit more sound underhood than manifolds do. I concur with the previous posts, pop the extra$$ and get stainless or coated headers, they will last MUCH longer...and I had never heard of headers causing a loss of low end torque. Unless the tubes were over large or the downpipe and exhaust were oversized as well. I would also think that headers would not be early on a list of engine mods. IMO, they are the kind of mod thats works in conjuction with other upgrades such as rockers, cam and larger TBs. I can agree that if you're running the L67 engine and you up the boost with a pulley change, then headers would be in order.